Astaxanthin found in Euglenoid eye spots also occurs elsewhere in

Options

A. Annelida
B. Cephalopoda
C. Crustacea
D. Insecta.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where astaxanthin, a pigment found in the eye spots of Euglena (a type of euglenoid), is also found.

2. **Identifying Euglena**: Euglena is a unicellular organism that possesses an eye spot, which helps it detect light. The eye spot contains the pigment astaxanthin.

3. **Exploring Astaxanthin**: Astaxanthin is a carotenoid pigment. Carotenoids are divided into two main groups: carotenes (like alpha and beta carotene) and xanthophylls (which include astaxanthin).

4. **Analyzing the Options**: The options given are Annelida, Cephalopoda, Crustacea, and Insecta. We need to determine which of these groups also contains astaxanthin.

5. **Researching the Groups**:
- **Annelida**: This group includes segmented worms and is not known for containing astaxanthin.
- **Cephalopoda**: This group includes squids and octopuses, which do not typically contain astaxanthin.
- **Crustacea**: This group includes crabs, lobsters, and shrimp, which are known to contain astaxanthin, especially in their shells and tissues.
- **Insecta**: While some insects may have carotenoids, they are not specifically known for containing astaxanthin.

6. **Conclusion**: Based on the information gathered, the correct answer is **Crustacea**, as astaxanthin is indeed found in this group.

**Final Answer**: Astaxanthin found in Euglenoid eye spots also occurs in **Crustacea**.

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